Battery? Alternator? Help!

[PuckHead]

Hey all,
Havn't been on the site for a couple weeks, but now find myself in need of help from the all-knowing, all-seeing Forum.

Last night while running some errands for the AWA, I noticed my battery light came on. The car didn't act any different than normal, and I just figured it came on because I was putting a big draw on the system with the heater on high, Rr. Def. on, stereo, and headlights.

After I got home, I remembered that I missed a stop, so after dinner I went back out to go to the stop I had missed and the car wouldn't start. Just sat there and clicked for a second. All the segments on the EATC were on, and the airbag light was on steady as well. It was too damn cold and dark out to worry about last night so I just let her sit in the driveway.

Today I go out and attempt to start her, and she turned over with no problem and fired right up. I went back in the house for ~15 minutes so she could warm up and when I went back outside, she had died and wouldn't start again, almost the same as last night. Just sat there and clicked.

A couple of hours later, I went out to try it again, and she fired up fine, but the tach wouldn't move, the EATC was lit up again, along with some other dummy lights. The worst part was that she would barely idle. I put my foot into her a little bit, and she sounded like she was only hitting a couple of cylinders. Didn't sound right and I shut her off quickly.

The battery is an Interstate, and is only a little over a year old, so I am thinking that it must be the alternator. I can't measure the voltage, or get a reading on the alt's output since I don't have a gauge, but with all this info given to you, what would you say?

Alternator or Battery?

Any info and opinions are welcomed!

Later!

 

[sdpatt]

The battery light is indicating that the alternator is not charging the battery. The battery is therefore discharged and in need of a healthy alternator or good battery charger to get it back to full charge, but only a new alternator will keep it there.

 

[SolidState]

when the altenator on my atx went, it did all kinds of funny things...

it actually put out barely enough voltage, but not enough current....I could leave it for a while and the car would start, but when driving it, it would be all over the place...shifting, lighting....etc

 

[masho95]

There are multiple conflicting statements that would disagree with Scott's altenator diagnosis. First if the batt light is on, check the single wire connector at the altenator. Second if the car just clicked while trying to start it, it's either a dead battery or a bad starter. If it was a bad battery (or even an altenator not charging the battery properly for that matter) it wouldn't start one time and then later start. That sounds more like a starter problem, especially with all the EATC and other lights working fine. As far as the tach not working, that's commonly a part of a CMP (camshaft position sensor) failure. Especially with is seeming like it's missing on a cylinder or two. Best bet run the codes and see what you come up with.

 

[EBOLA6]

-my tachometer did not work either!

-my car could barely idle at times too!

-other dummy lights came on too!

-my battery light came on too! (only 1 year old)

-changed out alternator...tada! Problem solved!

good luck

 

[masho95]

The worst part was that she would barely idle. I put my foot into her a little bit, and she sounded like she was only hitting a couple of cylinders. Didn't sound right and I shut her off quickly.

A failing altenator alone can't cause the car to feel like it's only hitting a couple of cylinders. Perhaps the altenator wasn't putting out enough power so a certain sensor or something was failing causing it to run bad, but I doubt it. At least run your codes to see what's in there.

 

[DHMag]

if it clicked while attempting to start, the batt has voltage and current, but not enough to engage the starter. the click you hear is more than likely from the starter solenoid on the DS fender well. i believe there is also a starter solenoid on the starter itself. been a while since ive had my starter off so i dont recall. might want to check for a loose power or ground wire. the small wires that attach to the battery cable terminals are important to have attached. without one of them, the car dont run, period. instead of awaiting for one of us to magically solve your problem, take remove the alternator and battery and have them tested. if they pass, try the starter. if it passes, im placing my bet on a loose connection.

 

[SolidState]

masho95:

The worst part was that she would barely idle. I put my foot into her a little bit, and she sounded like she was only hitting a couple of cylinders. Didn't sound right and I shut her off quickly.

A failing altenator alone can't cause the car to feel like it's only hitting a couple of cylinders. Perhaps the altenator wasn't putting out enough power so a certain sensor or something was failing causing it to run bad, but I doubt it. At least run your codes to see what's in there.

I disagree. When my altenator went south, I slowed to a stop at a railway crossing, and when I went to accelerate, there wasn't enough juice to run the car, missing, stupid shifting, all panel lights, flashing EATC....but as soon as I let off, things were ok....same thing when I started up a hill moments later...

 

[aaronsbiza]

I have a 95ATX and have replaced the alternator twice in three months. Both times the voltage regulator had gone astray. It included such syptoms as the battery light flickering, staying steady for a while, then blipping the throttle made the light turn off for a few minutes. I have been told there may be something in my electrical system causing this to happen to my alternators. But, my theroy is "duralast" beer thats why they come with a lifetime warranty, and only cost $185

 

[Off Road SHO]

SDPATT is correct. The reason it feels like you're running on two cylinders is because you are. It takes a lot of power (the 12 volt type) to operate the electric fuel injectors. Only the injectors with the least amount of resistance in them will fire their load when you don't have enough voltage to fire all 6.

Tom

 

[PuckHead]

First off, no codes came up other than the EGR (which I have known about), and the aftermarket EEPROM (my Ted B. LPM).

I managed to get voltage readings from the battery while off and while running.

Engine OFF: ~11.5 Volts
Engine ON: ~10.5 Volts

The voltmeter used was an old "Micronta" from Radio Shack, and it isn't digital, so the readings are +/- just a tad, but at no time did I get a reading of 12V or higher. I checked the connections and all seemed well.

She fired up straight-away when I turned the key and ran fine during the ~5 minutes I let her run while taking the readings with the voltmeter.

I'm still thinking Alternator, but damn, them things are spendy!

Found a used one at a junk yard. Do I take the chance?

Thanks for all the help!

Later!

 

[aaronsbiza]

I think your best course of action is to have your alternator tested at an autozone or other such store. Be sure that someone who knows what they are doing does the test, because when I had my alternator tested the tech assumed that the alternator was still good just because the voltage was reading normal, he failed to notice the glowing red light that was labeled defective. Just remember K.I.S.S.... Start with the alternator, have it tested and if it turns out ok then get into some more sophisticated tests.

 

[Rob94]

I just went through this same thing. Based on your numbers, the alternator is toast. The monkey's at AZ ordered me the wrong alternator...they ordered me the one YOU need. I was able to get my MTX alternator at my local rebuilders for $145. At Autozone, yours is $179 plus a $100 core. Expensive, but it is what you are gonna need to do to fix your problem.

 

[masho95]

Yep, looks like the altenator is toast. The output voltage with the car running is wayyy too low. It should be putting out something near 14V while running. Good luck with your repair.

 

[SolidState]

just as a FYI, the altenator in the ATX SHO is an Mitsubishi (I think...)

I picked one up BRAND NEW for 260 canadian...that would be about 180us....

 

[Off Road SHO]

Teg,

Where did you find such a deal, that's a great price. My local alternator re-builder, (who wouldn't rebuild my Mitsu 3.2 alternator) found one in Texas somewhere but it was going to cost me 260.00 USD plus shipping.

Tom

 

[SolidState]

local shop...

if you would like, I can check to see if they can still do that price...

 

[Off Road SHO]

Teg,

Yes I would like. Thanks,

Tom

 

[SHOZ123]

A good battery that has been discharged will tend to rejuvenate itself and allow for a restart after sitting (a couple of times). If the battery were bad it would not do this.

 

[Slo-Sho]

If anyone wants a good laugh, call up your local stealership for a 3.2 alternator. 2 years ago they told me ~$400!!